The present invention relates generally to robotic systems and, more particularly, to control schemes for robotic systems.
Modern manufacturing systems often employ robots to automate processes. These robotic systems can provide a number of benefits, such as increased production and precision. In semiconductor manufacturing, robotic systems enable the fabrication of sophisticated electronic devices. Because of the extreme costs associated with semiconductor manufacturing systems and the value of the resulting products, a key goal of these systems is the maximization of throughput.
In accordance with the present invention, techniques for robotic system control are provided. According to particular embodiments, these techniques increase throughput of robotic systems in comparison with previous techniques.
According to a particular embodiment for calculating a control schedule for a robot within a fabrication system, a method determines operating characteristics for steps in a fabrication process, the operating characteristics comprising a robot movement matrix for movements between a plurality of processing stations and processing times for each of the processing stations. The method further identifies a plurality of control schedules each detailing a process for a robot to shuttle wafers between the processing stations, determines fitness for each of the control schedules using the operating characteristics, and mates the control schedules according to the fitness determined for each control schedule to create a resulting generation of control schedules. The method iterates the fitness determining and the mating for a plurality of resulting generations and then selects a chosen control schedule from a final one of the resulting generations based on fitness. Using the chosen control schedule, the method operates the robot.
Embodiments of the invention provide various technical advantages. These techniques, when appropriately implemented, can enhance productivity of robotic systems. Due to the high value of fabricated wafers, even very small improvements in average process times can greatly increase profitability over time. Moreover, certain embodiments provide for self-tuning of robotic systems in response to measured operating characteristics. This can potentially provide even greater productivity increases.
Other technical advantages of the present invention will be readily apparent to one skilled in the art from the following figures, descriptions, and claims. Moreover, while specific advantages have been enumerated above, various embodiments may include all, some, or none of the enumerated advantages.